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https://www.readbyqxmd.com/read/28227463/hemodynamic-effects-of-synchronizing-an-intra-aortic-vad-in-reverse-rotation-control-with-left-ventricle-a-mock-loop-study
#1
Yaxin Wang, P Alex Smith, Daniel L Timms, Po-Lin Hsu, Richard A McMahon, Yaxin Wang, P Alex Smith, Daniel L Timms, Po-Lin Hsu, Richard A McMahon, Richard A McMahon, Daniel L Timms, Po-Lin Hsu, Yaxin Wang, P Alex Smith
The IntraVAD is an intra-aortic left ventricular assist device (LVAD) to be located in the ascending aorta. In order to enhance unloading and promote coronary flow for the left ventricle (LV), an operating mechanism, reverse-rotation control (RRc) mode, has been developed for the IntraVAD and tested in vitro in a mock circulation loop (MCL). The RRc mode consists of forward rotation (FR) and reverse rotation (RR). The synchronization between the IntraVAD and the LV was studied to offload the ventricle more effectively and to improve myocardial perfusion...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28223475/reduced-first-phase-ejection-fraction-and-sustained-myocardial-wall-stress-in-hypertensive-patients-with-diastolic-dysfunction-a-manifestation-of-impaired-shortening-deactivation-that-links-systolic-to-diastolic-dysfunction-and-preserves-systolic-ejection-fraction
#2
Haotian Gu, Ye Li, Henry Fok, John Simpson, Jonathan C Kentish, Ajay M Shah, Philip J Chowienczyk
Impaired shortening deactivation of cardiac myocytes could sustain myocardial contraction, preserving ejection fraction at the expense of diastolic dysfunction. We examined the relationship between first-phase ejection fraction (EF1), the fraction of left ventricular volume ejected from the start of systole to the time of the first peak in left ventricular pressure (corresponding to the time of maximal ventricular shortening) to the duration of myocardial contraction and diastolic function in patients with hypertension (n=163), and varying degrees of diastolic dysfunction...
February 21, 2017: Hypertension
https://www.readbyqxmd.com/read/28204860/left-ventricular-systolic-dysfunction-during-septic-shock-the-role-of-loading-conditions
#3
Florence Boissier, Keyvan Razazi, Aurélien Seemann, Alexandre Bedet, Arnaud W Thille, Nicolas de Prost, Pascal Lim, Christian Brun-Buisson, Armand Mekontso Dessap
PURPOSE: The clinical significance of septic myocardial dysfunction is controversial, a fact that may be explained by the influence of loading conditions. Many indices may be useful to characterize cardiac function during septic shock, but their feasibility and physiological coherence in the clinical setting are unknown. METHODS: Hemodynamic and echocardiographic data with tissue Doppler and speckle tracking were prospectively recorded on the first 3 days of human septic shock...
February 15, 2017: Intensive Care Medicine
https://www.readbyqxmd.com/read/28197291/postoperative-right-ventricular-failure-in-cardiac-surgery
#4
REVIEW
Victor H Nieto Estrada, Daniel L Molano Franco, Albert A Valencia Moreno, Jose A Rojas Gambasica, Cristian C Cortes Nunez
Two cases of patients that developed right ventricular failure (RVF) after cardiac valve surgery are presented with a narrative revision of the literature. RVF involves a great challenge due to the severity of this condition; it has a low incidence among non-congenital cardiac surgery patients, is more likely associated with cardiovascular and pulmonary complications related to cardiopulmonary bypass (CPB), and is a cause of acute graft failure and of a higher early mortality in cardiac transplant. The morphologic and hemodynamic characteristics of the right ventricle and some specific factors that breed pulmonary hypertension after cardiac surgery are in favor of the onset of RVF...
December 2016: Cardiology Research
https://www.readbyqxmd.com/read/28195341/left-ventricular-systolic-function-is-associated-to-sympathetic-nervous-activity-and-markers-of-inflammation-in-cirrhosis
#5
Raquel Yotti, Cristina Ripoll, Yolanda Benito, Maria Vega Catalina, Jaime Elízaga, Diego Rincón, Francisco Fernández-Avilés, Javier Bermejo, Rafael Bañares
: An accurate evaluation of cardiac function in patients with cirrhosis remains a challenge. We used robust echocardiographic indices to characterize LV systolic function and its relationship to activation of the sympathetic nervous system (SNS) and inflammation in 59 patients cirrhosis and 59 age-matched controls. Aditionally, in eleven patients we withdrew betablockers and diuretics and used phenylephrine and albumin infusion to evaluate the response to acute afterload and preload changes (interventional substudy)...
February 13, 2017: Hepatology: Official Journal of the American Association for the Study of Liver Diseases
https://www.readbyqxmd.com/read/28194115/low-level-laser-application-in-the-early-myocardial-infarction-stage-has-no-beneficial-role-in-heart-failure
#6
Martha T Manchini, Ednei L Antônio, José Antônio Silva Junior, Paulo de Tarso C de Carvalho, Regiane Albertini, Fernando C Pereira, Regiane Feliciano, Jairo Montemor, Stella S Vieira, Vanessa Grandinetti, Amanda Yoshizaki, Marcio Chaves, Móises P da Silva, Rafael do Nascimento de Lima, Danilo S Bocalini, Bruno L de Melo, Paulo J F Tucci, Andrey J Serra
Low-level laser therapy (LLLT) has been targeted as a promising approach that can mitigate post-infarction cardiac remodeling. There is some interesting evidence showing that the beneficial role of the LLLT could persist long-term even after the end of the application, but it remains to be systematically evaluated. Therefore, the present study aimed to test the hypothesis that LLLT beneficial effects in the early post-infarction cardiac remodeling could remain in overt heart failure even with the disruption of irradiations...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28193800/cardiovascular-and-ventilatory-consequences-of-laparoscopic-surgery
#7
Tamara M Atkinson, George D Giraud, Brandon M Togioka, Daniel B Jones, Joaquin E Cigarroa
Although laparoscopic surgery accounts for >2 million surgical procedures every year, the current preoperative risk scores and guidelines do not adequately assess the risks of laparoscopy. In general, laparoscopic procedures have a lower risk of morbidity and mortality compared with operations requiring a midline laparotomy. During laparoscopic surgery, carbon dioxide insufflation may produce significant hemodynamic and ventilatory consequences such as increased intraabdominal pressure and hypercarbia. Hemodynamic insults secondary to increased intraabdominal pressure include increased afterload and preload and decreased cardiac output, whereas ventilatory consequences include increased airway pressures, hypercarbia, and decreased pulmonary compliance...
February 14, 2017: Circulation
https://www.readbyqxmd.com/read/28160954/management-of-sepsis-in-patients-with-pulmonary-arterial-hypertension-in-the-intensive-care-unit
#8
REVIEW
Todd M Tartavoulle
Pulmonary arterial hypertension is a lethal condition, and the management of sepsis in patients with pulmonary arterial hypertension is challenging. As the disease progresses, the right ventricle is susceptible to failure due to a high pulmonary vascular resistance. The limited ability of the right ventricle to increase cardiac output in septic shock makes it difficult to deliver oxygen to the organ and tissues. Intravascular volume replacement and vasoactive drugs should only be considered after a thorough assessment...
March 2017: Critical Care Nursing Clinics of North America
https://www.readbyqxmd.com/read/28159826/aortic-waveform-analysis-to-individualize-treatment-in-heart-failure
#9
Peter Wohlfahrt, Vojtech Melenovsky, Margaret M Redfield, Thomas P Olson, Grace Lin, Sahar S Abdelmoneim, Bernhard Hametner, Siegfried Wassertheurer, Barry A Borlaug
BACKGROUND: Afterload reduction is a cornerstone in the management of patients with heart failure (HF) and reduced ejection fraction. However, arterial load and the effect of HF therapies on afterload might vary between individuals. Tailoring vasoactive medicines to patients with HF based upon better understanding of arterial afterload may enable better individualization of therapy. METHODS AND RESULTS: Subjects with HF and reduced ejection fraction underwent aggressive titration of vasoactive HF therapies with assessment of central aortic waveforms analyzed using pulse wave, wave separation, and arterial reservoir models...
February 2017: Circulation. Heart Failure
https://www.readbyqxmd.com/read/28156516/template-based-high-dose-rate-endobronchial-brachytherapy-for-palliation-of-previously-irradiated-obstructive-lung-lesions
#10
Hsienchang Chiu, Michael Ryan Folkert
: 174 Background: Local progression after external beam radiation therapy (RT) for lung cancer may result in clinical compromise from bleeding and/or airway obstruction, and additional RT may be precluded by radiation tolerance. High-dose-rate (HDR) endobronchial brachytherapy (EBT) is an effective salvage treatment for airway obstruction and/or bleeding, but requires significant time and resources; planning and treatment are performed bronchoscopically under anesthesia. We sought to reduce procedure and anesthesia time for EBT through template-based planning...
October 9, 2016: Journal of Clinical Oncology: Official Journal of the American Society of Clinical Oncology
https://www.readbyqxmd.com/read/28145285/dedicated-high-dose-rate-192-ir-brachytherapy-radiation-fields-for-in-vitro-cell-exposures-at-variable-source-target-cell-distances-killing-of-mammalian-cells-depends-on-temporal-dose-rate-fluctuation
#11
Cornelia Veigel, Günther H Hartmann, Peter Fritz, Jürgen Debus, Klaus-Josef Weber
Afterloading brachytherapy is conducted by the stepwise movement of a radioactive source through surgically implanted applicator tubes where at predefined dwell positions calculated dwell times optimize spatial dose delivery with respect to a planned dose level. The temporal exposure pattern exhibits drastic fluctuations in dose rate at a given coordinate and within a single treatment session because of the discontinuous and repeated source movement into the target volume. This could potentially affect biological response...
February 1, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28125466/comparison-of-hemodynamic-performance-and-clinical-results-with-evaheart-versus-heartmate-ii
#12
Yorihiko Matsumoto, Tomoyuki Fujita, Satsuki Fukushima, Hiroki Hata, Yusuke Shimahara, Yuta Kume, Kizuku Yamashita, Kensuke Kuroda, Seiko Nakajima, Takuma Sato, Osamu Seguchi, Masanobu Yanase, Norihide Fukushima, Hideyuki Shimizu, Junjiro Kobayashi
This study aimed to compare the hemodynamic performance and clinical results of the EVAHEART and HeartMate II left ventricular assist devices (LVADs). From 2007 to 2016, 14 patients received EVAHEART and 28 received HeartMate II at our center. Early survival, driveline infection and neurological events were evaluated. Hemodynamic performance was evaluated with transthoracic echocardiography and right heart catheterization. Mean follow-up was 35.5 ± 14.8 months for EVAHEART, and 29.8 ± 6.5 months for HeartMate II...
January 23, 2017: ASAIO Journal: a Peer-reviewed Journal of the American Society for Artificial Internal Organs
https://www.readbyqxmd.com/read/28115510/abnormal-wave-reflections-and-left-ventricular-hypertrophy-late-after-coarctation-of-the-aorta-repair
#13
Michael A Quail, Rebekah Short, Bejal Pandya, Jennifer A Steeden, Abbas Khushnood, Andrew M Taylor, Patrick Segers, Vivek Muthurangu
Patients with repaired coarctation of the aorta are thought to have increased afterload due to abnormalities in vessel structure and function. We have developed a novel cardiovascular magnetic resonance protocol that allows assessment of central hemodynamics, including central aortic systolic blood pressure, resistance, total arterial compliance, pulse wave velocity, and wave reflections. The main study aims were to (1) characterize group differences in central aortic systolic blood pressure and peripheral systolic blood pressure, (2) comprehensively evaluate afterload (including wave reflections) in the 2 groups, and (3) identify possible biomarkers among covariates associated with elevated left ventricular mass (LVM)...
March 2017: Hypertension
https://www.readbyqxmd.com/read/28108832/beat-by-beat-assessment-of-cardiac-afterload-using-descending-aortic-velocity-pressure-loop-during-general-anesthesia-a-pilot-study
#14
Fabrice Vallée, Arthur Le Gall, Jona Joachim, Olivier Passouant, Joaquim Matéo, Arnaud Mari, Sandrine Millasseau, Alexandre Mebazaa, Etienne Gayat
Continuous cardiac afterload evaluation could represent a useful tool during general anesthesia (GA) to titrate vasopressor effect. Using beat to beat descending aortic pressure(P)/flow velocity(U) loop obtained from esophageal Doppler and femoral pressure signals might allow to track afterload changes. Methods We defined three angles characterizing the PU loop (alpha, beta and Global After-Load Angle (GALA)). Augmentation index (AIx) and total arterial compliance (Ctot) were measured via radial tonometry. Peripheral Vascular Resistances (PVR) were also calculated...
January 20, 2017: Journal of Clinical Monitoring and Computing
https://www.readbyqxmd.com/read/28107308/acute-right-heart-failure-after-hemorrhagic-shock-and-trauma-pneumonectomy-a-management-approach-a-blinded-randomized-controlled-animal-trial-using-inhaled-nitric-oxide
#15
Andrea L Lubitz, Lars O Sjoholm, Amy Goldberg, Abhijit Pathak, Thomas Santora, Thomas E Sharp, Markus Wallner, Remus M Berretta, Lauren A Poole, Jichuan Wu, Marla R Wolfson
BACKGROUND: Hemorrhagic shock and pneumonectomy causes an acute increase in pulmonary vascular resistance (PVR). The increase in PVR and right ventricular (RV) afterload leads to acute RV failure, thus reducing left ventricular (LV) preload and output. Inhaled nitric oxide (iNO) lowers PVR by relaxing pulmonary arterial smooth muscle without remarkable systemic vascular effects. We hypothesized that with hemorrhagic shock and pneumonectomy, iNO can be used to decrease PVR and mitigate right heart failure...
2017: Journal of Trauma and Acute Care Surgery
https://www.readbyqxmd.com/read/28100164/relation-between-arterial-stiffness-and-aerobic-capacity-importance-of-proximal-aortic-stiffness
#16
Tsubasa Tomoto, Seiji Maeda, Jun Sugawara
Brachial-ankle pulse wave velocity (baPWV) has become a popular modality of arterial stiffness measurement. However, its projected arterial segment does not include the proximal aorta which plays important roles for attenuating cardiac pulsation and reducing afterload. We hypothesised that aerobic capacity would be more strongly associated with PWV including the proximal aorta than that omitting the proximal aorta. To test our hypothesis, we compared the association between aerobic capacity and arterial stiffness parameters omitting vs...
January 19, 2017: European Journal of Sport Science
https://www.readbyqxmd.com/read/28099680/novel-putative-pharmacologic-therapies-to-protect-the-right-ventricle-in-pulmonary-hypertension-a-review-of-current-literature
#17
REVIEW
Gerald J Maarman, Rainer Schulz, Karen Sliwa, Ralph Schermuly, Sandrine Lecour
Pulmonary hypertension (PH) is defined by elevated mean pulmonary artery pressure following the pathologic remodelling of small pulmonary arteries. An increase in right ventricular (RV) afterload results in RV hypertrophy and RV failure. The pathophysiology of PH, and RV remodelling in particular, are not well understood, thus explaining, at least in part, why current PH therapies have a limited effect. Existing therapies mostly target the pulmonary circulation. Because the remodelled RV fails to support normal cardiac function, patients eventually succumb from RV failure...
January 18, 2017: British Journal of Pharmacology
https://www.readbyqxmd.com/read/28098356/mechano-chemo-transduction-in-cardiac-myocytes
#18
Ye Chen-Izu, Leighton T Izu
The heart has the ability to adjust to changing mechanical loads. The Frank-Starling law and the Anrep effect describe exquisite intrinsic mechanisms the heart has for autoregulating the force of contraction to maintain cardiac output under preload and afterload. Although these mechanisms have been known for more than a century, their cellular and molecular underpinnings are still debated. How does the cardiac myocyte sense a change in preload or afterload? How does the myocyte adjust its response to compensate for such changes? In cardiac myocytes Ca(2+) is a crucial regulator of contractile force and in this review we compare and contrast recent results from different labs that address two important questions...
January 18, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/28090307/hemodynamic-response-to-treatment-of-iron-deficiency-anemia-in-pulmonary-arterial-hypertension-longitudinal-insights-from-an-implantable-hemodynamic-monitor
#19
Muddassir Mehmood, Richa Agarwal, Amresh Raina, Priscilla Correa-Jaque, Raymond L Benza
Despite new therapeutic options, pulmonary arterial hypertension (PAH) remains a progressive disease associated with substantial morbidity and mortality. As such, additional strategies for monitoring and adjunctive management of this disease are important. A 59-year-old woman with scleroderma-associated PAH received an implantable hemodynamic monitor (IHM) as part of a research protocol at our institution. Pulmonary artery pressures, heart rate, and cardiac output (sensor-based algorithm) were measured on a daily basis, and parameters of right ventricular (RV) performance and afterload were calculated...
December 2016: Pulmonary Circulation
https://www.readbyqxmd.com/read/28090292/a-new-look-at-bronchopulmonary-dysplasia-postcapillary-pathophysiology-and-cardiac-dysfunction
#20
Arvind Sehgal, Andra Malikiwi, Eldho Paul, Kenneth Tan, Samuel Menahem
Pulmonary hypertension (PH) and right ventricular function are the focus of cardiovascular effects of bronchopulmonary dysplasia (BPD). We assessed cardiac indexes reflecting systemic afterload and pulmonary venous back pressure as pathophysiologic factors. Cardiac parameters were measured by conventional echocardiography in 20 preterm infants with severe BPD and compared with those of 10 preterm infants with no BPD and 20 healthy term infants. In infants with severe BPD, PH was noted in 5 (25%) by tricuspid regurgitation Doppler jet ≥2...
December 2016: Pulmonary Circulation
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